Stax SR-007Mk2/SR-007A port mod

[dvse]

Insufficient flexibility of strain relief is definitely a problem, but why would they then change the way it's attached to the cup?

Could the smaller spring be due to considerably thicker earpad material? Although the difference appears to be too big for that alone.

[spritzer]

Insufficient flexibility of strain relief is definitely a problem, but why would they then change the way it's attached to the cup?

The silver ribbons breaking is also a known fault so they just killed two birds with one stone. The old entry wouldn't have worked as a port either as the transfer of air isn't as direct.

Could the smaller spring be due to considerably thicker earpad material? Although the difference appears to be too big for that alone.

I don't think so. The older springs are tough to properly insert into the pads due to their size and they grasp the sides firmly if properly installed. That means the bend on the center piece will control how tall the pads will be, even under full pressure. The new springs are very loose inside the pads (either version as they are basically the same) but they sit much higher.

One thing to note is that the material in the springs is very strong so it takes quite a bit of force to compress them. It will take even more to change the shape so I'll have to check with Stax to see if I can buy a small stock of the Mk1 model.

[spritzer]

Now that I've spent a week with the Mk1 springs in place there isn't enough of an improvement to call it a day. Next step was to modify the Mk2 springs so that they were 100mm across and so that they didn't lift the pads quite as much, basically make them like the Mk1 springs. It was relatively easy to do by hand and I fitted brand new Mk1 pads while I was at it.

On a direct A-B comparison to the Mk1 the sound is much closer now with the A/Mk2 a bit more forward and the midrange a wee bit colder. There is still some honk but only time will tell if I can live with it or not.

I also compared the Mk1 and Mk2 earpads while I had the phones open. The new leather used on the Mk2 pads is indeed very nice unlike the Mk1 units they aren't all leather. The lip used to hold the pads to the phones is now made of vinyl which is much looser with even less tensile strength. This makes the phones easier to assemble and the pads deeper but it's a clear compromise over the snug fit of the Mk1 pads.

The new pads are stiffer then a brand new set of Mk1 pads (possibly to make the last longer?) and foam construction and materials are different. The angle of the pads is also smaller on the Mk2 compared to the Mk1.

I will now run them like this for another week to see how it is but the next step is far more drastic, a driver swap between a mk1 and my A which is something I'm not looking forward to...

[spritzer]

I've now lived with the latest mods for some two weeks and I think I've reached my goal of making these phones worthy of the Omega name. I did go back to the Mk2 springs but I bent them to about 110-115mm and I fitted Mk1 foam inside the Mk2 pads. The springs stick out a bit under the pads but the extra width was necessary do to the crappy pleather Stax used on the Mk2 outside flange which holds the pads in place. It's much looser then the leather in the Mk1 pads so the extra width of the springs clamps the pads in place and forces them to sit closer to the drivers. I also changed the angle of the center pin on the springs to make them stand out less so this works in tandem to force the pads to sit closer to the drivers.

I also swapped the foam inside the Mk2 pads with foam from a fresh set of Mk1 pads to make them a bit softer. I didn't do this in isolation from the other mods to the springs so I'm not quite sure if this had any effect. I may reverse it later on but the effect should be very subtle if non-existent but this isn't verified.

The end result is what I set out to do, accurate bass response with zero midbass hump and the midrange honk removed. They don't sound completely like the Mk1 though, the bass is a bit lighter on it's feet and the midrange more forward which makes them work a whole lot better on "lesser" amps like the SRM-1, T1 and 007t. I will reserve final judgment until I get to hear them on a Blue Hawaii again with the rest of my Omegas but as it stands right now I quite like them.

[catscratch]

Nice! This is good news for those who can't get a Mk1, or for when its price inevitably shoots up.

[Anders]

Thanks, I have saved it with pictures for future needs, need not worry so much about my Mk I and can sleep a little better

[2deadeyes]

First post even though I've been lurking around for quite some time. Many thanks to Birgir for directing me to this detailed guide - I'll definitely be taking a shot @ it as soon as I get some blutack.

P.S. sup fellas?

[jinp6301]

hey! nice to see you here!

[Blueman2]

I know this is an old topic, but I wanted to add some pictures of the latest sr-007 so that people can see if there are any differences.  I did the blue-tac mod on the port and increased the spring to 105mm and flattened it as recommended.  I inserted the spring as per the old -007 model as shown in the instructions (credit to spritzer for the instructions sheet picture).  The difference in bass was actually quite moderate.  It did help with bass response, but the change was subtle.  Which is really all I wanted.  No issues with the Stax fart at all so far.  See attached.  This was purchased Dec 15 2017 directly from Stax in Japan.  

 

Edited December 27, 2017 by Blueman2